<template>
  <div class="q-pa-md">
    <q-table
      flat
      color="primary"
      class="cross_table my-sticky-header-column-table"
      separator="cell"
      title="多列头演示"
      :data="data"
      :columns="columns"
      row-key="name"
    >
      <template v-slot:header="props">
        <template>
          <q-tr :props="props" v-for="(headList,index) in multipleHeadList" :key="index">
            <q-th v-for="head in headList" :key="head.name" :colspan="head.colSpan"
            :rowspan="head.rowSpan" class="text-center ">
              {{head.name}}</q-th>
          </q-tr>
        </template>
      </template>
    </q-table>
  </div>
</template>

<script>

export default {
  data() {
    return {
      selected: [],
      multipleHeadList: [
        [{ name: '第一级表头1', colSpan: 2, rowSpan: 1 }, { name: '第一级表头2', colSpan: 1, rowSpan: 2 }, { name: '第一级表头2', colSpan: 1, rowSpan: 2 }, { name: '第一级表头2', colSpan: 1, rowSpan: 2 }, { name: '第一级表头2', colSpan: 1, rowSpan: 2 }, { name: '第一级表头2', colSpan: 1, rowSpan: 2 }, { name: '第一级表头2', colSpan: 1, rowSpan: 2 }],
        [{ name: '第二级表头1', colSpan: 1, rowSpan: 1 }, { name: '第二级表头2', colSpan: 1, rowSpan: 1 }],
      ],
      columns: [
        {
          name: 'name',
          required: true,
          label: 'Dessert (100g serving)',
          align: 'left',
          field: (row) => row.name,
          format: (val) => `${val}`,
          sortable: true,
          style: 'width: 180px',
          headerStyle: 'width: 180px',
        },
        {
          name: 'calories',
          align: 'center',
          label: 'Calories',
          field: 'calories',
          sortable: true,
          style: 'width: 180px',
          headerStyle: 'width: 180px',
        },
        {
          name: 'fat', label: 'Fat (g)', field: 'fat', sortable: true,
        },
        {
          name: 'carbs', label: 'Carbs (g)', field: 'carbs', sortable: true,
        },
        {
          name: 'protein',
          label: 'Protein (g)',
          field: 'protein',
          sortable: true,
        },
        {
          name: 'sodium',
          label: 'Sodium (mg)',
          field: 'sodium',
          sortable: true,
        },
        {
          name: 'calcium',
          label: 'Calcium (%)',
          field: 'calcium',
          sortable: true,
          sort: (a, b) => parseInt(a, 10) - parseInt(b, 10),
        },
        {
          name: 'iron',
          label: 'Iron (%)',
          field: 'iron',
          sortable: true,
          sort: (a, b) => parseInt(a, 10) - parseInt(b, 10),
        },
      ],

      data: [
        {
          name: 'Frozen Yogurt',
          calories: 159,
          fat: 6.0,
          carbs: 24,
          protein: 4.0,
          sodium: 87,
          calcium: '14%',
          iron: '1%',
        },
        {
          name: 'Ice cream sandwich',
          calories: 237,
          fat: 9.0,
          carbs: 37,
          protein: 4.3,
          sodium: 129,
          calcium: '8%',
          iron: '1%',
        },
        {
          name: 'Eclair',
          calories: 262,
          fat: 16.0,
          carbs: 23,
          protein: 6.0,
          sodium: 337,
          calcium: '6%',
          iron: '7%',
        },
        {
          name: 'Cupcake',
          calories: 305,
          fat: 3.7,
          carbs: 67,
          protein: 4.3,
          sodium: 413,
          calcium: '3%',
          iron: '8%',
        },
        {
          name: 'Gingerbread',
          calories: 356,
          fat: 16.0,
          carbs: 49,
          protein: 3.9,
          sodium: 327,
          calcium: '7%',
          iron: '16%',
        },
        {
          name: 'Jelly bean',
          calories: 375,
          fat: 0.0,
          carbs: 94,
          protein: 0.0,
          sodium: 50,
          calcium: '0%',
          iron: '0%',
        },
        {
          name: 'Lollipop',
          calories: 392,
          fat: 0.2,
          carbs: 98,
          protein: 0,
          sodium: 38,
          calcium: '0%',
          iron: '2%',
        },
        {
          name: 'Honeycomb',
          calories: 408,
          fat: 3.2,
          carbs: 87,
          protein: 6.5,
          sodium: 562,
          calcium: '0%',
          iron: '45%',
        },
        {
          name: 'Donut',
          calories: 452,
          fat: 25.0,
          carbs: 51,
          protein: 4.9,
          sodium: 326,
          calcium: '2%',
          iron: '22%',
        },
        {
          name: 'KitKat',
          calories: 518,
          fat: 26.0,
          carbs: 65,
          protein: 7,
          sodium: 54,
          calcium: '12%',
          iron: '6%',
        },
      ],
    };
  },
};
</script>

<style lang="stylus">
.my-sticky-header-column-table
  height: 310px
  max-width: 600px

  td:first-child, td:nth-child(2)
    background-color: #c1f4cd !important

  tr th
    position: sticky
    /* higher than z-index for td below */
    z-index: 2
    /* bg color is important; just specify one */
    background: $primary

  thead tr:last-child th
    top: 48px
    z-index: 3
  thead tr:first-child th
    top: 0
    z-index: 1
  thead tr:nth-child(2) th
    top: 96px;
    z-index: 1

  thead tr:nth-child(2) th
    top: 0
    z-index: 1

  tr:first-child th:first-child
    z-index: 3
  tr:nth-child(2) th:nth-child(2)
    z-index: 3

  td:first-child
    z-index: 1
  td:nth-child(2)
    z-index: 1

  td:first-child, th:first-child
    position: sticky
    left: 0

  td:nth-child(2)
    position: sticky
    left: 147px
  th:nth-child(2)
    position: sticky
    left: 147px
    top: 96px;
</style>
